Evaluation of image quality at the detector’s edge of dedicated breast positron emission tomography

Abstract Background: Using phantoms and clinical studies in prone hanging breast imaging, we assessed the image quality of a commercially available dedicated breast PET (dbPET) at the detector's edge, where mammary glands near the chest wall are located. These are compared to supine PET/CT breast images of the same clinical subjects.Methods: A breast phantom with four spheres (16, 10, 7.5, and 5 mm diameter) was filled with 18F-fluorodeoxyglucose solution (sphere-to-background activity concentration ratio, 8:1). The spheres occupied five different positions from the top edge to the centre of the detector and were scanned for 5 min in each position. Reconstructed images were visually evaluated, and the contrast-to-noise ratio (CNR), contrast recovery coefficient (CRC) for the 5-mm sphere, and coefficient of variation of the background (CVB) were calculated. Subsequently, clinical images obtained with standard supine PET/CT and prone dbPET were retrospectively analysed. Tumour-to-background ratios (TBRs) between breast cancer near the chest wall (close to the detector’s edge; peripheral group) and at other locations (non-peripheral group) were compared. The TBR of each lesion was compared between dbPET and PET/CT.Results: Closer to the detector’s edge, the CNR and CRC decreased while the CVB increased in the phantom study for all sphere sizes. The disadvantages of this placement were visually confirmed. Regarding clinical images, TBR of dbPET was significantly higher than that of PET/CT in both the peripheral (12.38±6.41 vs 6.73±3.5, p=0.0006) and non-peripheral (12.44±5.94 vs 7.71±7.1, p=0.0183) groups. There was no significant difference in TBR of dbPET between the peripheral and non-peripheral groups.Conclusion: The phantom study revealed poorer image quality at <2 cm distance from the detector's edge than at other more central parts. In clinical studies, however, the visibility of breast lesions with dbPET was the same regardless of the lesion position, and it was higher than that in PET/CT. dbPET has a great potential for detecting breast lesions near the chest wall if they are at least 2 cm from the edge of the FOV, even in young women with small breasts.

Download Full-text

Evaluation of image quality at the detector’s edge of dedicated breast positron emission tomography

EJNMMI Physics ◽

10.1186/s40658-020-00351-6 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Yoko Satoh ◽

Utaroh Motosugi ◽

Masamichi Imai ◽

Yoshie Omiya ◽

Hiroshi Onishi

Keyword(s):

Image Quality ◽

Chest Wall ◽

Clinical Studies ◽

Breast Imaging ◽

Phantom Study ◽

Breast Lesions ◽

Clinical Images ◽

Dedicated Breast Pet ◽

Pet Ct ◽

Significant Difference

Abstract Background Using phantoms and clinical studies in prone hanging breast imaging, we assessed the image quality of a commercially available dedicated breast PET (dbPET) at the detector’s edge, where mammary glands near the chest wall are located. These are compared to supine PET/CT breast images of the same clinical subjects. Methods A breast phantom with four spheres (16-, 10-, 7.5-, and 5-mm diameter) was filled with 18F-fluorodeoxyglucose solution (sphere-to-background activity concentration ratio, 8:1). The spheres occupied five different positions from the top edge to the centre of the detector and were scanned for 5 min in each position. Reconstructed images were visually evaluated, and the contrast-to-noise ratio (CNR), contrast recovery coefficient (CRC) for all spheres, and coefficient of variation of the background (CVB) were calculated. Subsequently, clinical images obtained with standard supine PET/CT and prone dbPET were retrospectively analysed. Tumour-to-background ratios (TBRs) between breast cancer near the chest wall (close to the detector’s edge; peripheral group) and at other locations (non-peripheral group) were compared. The TBR of each lesion was compared between dbPET and PET/CT. Results Closer to the detector’s edge, the CNR and CRC of all spheres decreased while the CVB increased in the phantom study. The disadvantages of this placement were visually confirmed. Regarding clinical images, TBR of dbPET was significantly higher than that of PET/CT in both the peripheral (12.38 ± 6.41 vs 6.73 ± 3.5, p = 0.0006) and non-peripheral (12.44 ± 5.94 vs 7.71 ± 7.1, p = 0.0183) groups. There was no significant difference in TBR of dbPET between the peripheral and non-peripheral groups. Conclusion The phantom study revealed poorer image quality at < 2-cm distance from the detector’s edge than at other more central parts. In clinical studies, however, the visibility of breast lesions with dbPET was the same regardless of the lesion position, and it was higher than that in PET/CT. dbPET has a great potential for detecting breast lesions near the chest wall if they are at least 2 cm from the edge of the FOV, even in young women with small breasts.

Download Full-text

Evaluation of image quality at the detector’s edge of dedicated breast positron emission tomography

10.21203/rs.3.rs-21524/v3 ◽

2020 ◽

Author(s):

Yoko Satoh ◽

Utaroh Motosugi ◽

Masamichi Imai ◽

Yoshie Omiya ◽

Hiroshi Onishi

Keyword(s):

Positron Emission Tomography ◽

Image Quality ◽

Chest Wall ◽

Clinical Studies ◽

Phantom Study ◽

Emission Tomography ◽

Breast Lesions ◽

Clinical Images ◽

Positron Emission ◽

Pet Ct

Abstract Background: The dedicated breast positron emission tomography (dbPET) scanner (Elmamo, Shimadzu, Kyoto, Japan) has received approval from the Japanese Pharmaceutical Affairs Law and is commercially available in Japan. We assessed image quality of dbPET at the detector's edge, where the mammary glands near the chest wall are located in phantom and clinical studies.Methods: A breast phantom with four spheres (16, 10, 7.5, and 5 mm diameter) was filled with 18F-fluorodeoxyglucose solution (sphere-to-background ratio, 8:1). The spheres occupied five different positions from the top edge to the centre of the detector and were scanned for 5 min in each position. Reconstructed images were visually evaluated, and the contrast-to-noise ratio (CNR), contrast recovery coefficient (CRC) for the 5-mm sphere, and coefficient of variation of the background (CVB) were calculated. Subsequently, clinical images obtained with standard spine PET/CT and prone dbPET were retrospectively analysed. Tumour-to-background ratios (TBRs) between breast cancer near the chest wall (close to the detector’s edge; peripheral group) and at other locations (non-peripheral group) were compared. The TBR of each lesion was compared between dbPET and PET/computed tomography (CT).Results: Closer to the detector’s edge, the CNR and CRC decreased while the CVB increased in the phantom study. The disadvantages of this placement were visually confirmed. Regarding clinical images, TBR of dbPET was significantly higher than that of PET/CT in both the peripheral (12.38±6.41 vs 6.73±3.5, p=0.0006) and non-peripheral (12.44±5.94 vs 7.71±7.1, p=0.0183) groups. There was no significant difference in TBR of dbPET between the peripheral and non-peripheral groups (12.4±6.4 vs 12.4±5.9, p=0.8261).Conclusion: The phantom study revealed poorer image quality closer to the detector edge at a depth of <2 cm from the detector's edge than at other more central parts. In clinical studies, however, the visibility of breast lesions with dbPET was the same regardless of the lesion position, and it was higher than that in PET/CT. dbPET has a great potential for detecting breast lesions near the chest wall if they are at least 2 cm from the edge of the FOV, even in young women with small breasts.

Download Full-text

Evaluation of image quality at the detector’s edge of dedicated breast positron emission tomography

10.21203/rs.3.rs-21524/v2 ◽

2020 ◽

Author(s):

Yoko Satoh ◽

Utaroh Motosugi ◽

Masamichi Imai ◽

Yoshie Omiya ◽

Hiroshi Onishi

Keyword(s):

Positron Emission Tomography ◽

Image Quality ◽

Chest Wall ◽

Clinical Studies ◽

Phantom Study ◽

Emission Tomography ◽

Clinical Images ◽

Positron Emission ◽

Pet Ct ◽

Significant Difference

Abstract Background: We assessed image quality of dedicated breast positron emission tomography (dbPET) at the detector's edge by phantom and clinical studies.Methods: A breast phantom with four spheres (16, 10, 7.5, and 5 mm diameter) was filled with 18F-fluorodeoxyglucose solution (sphere-to-background ratio, 8:1). The spheres occupied five different positions from the top edge to the centre of the detector and were scanned for 5 min in each position. Reconstructed images were visually evaluated, and % background variability (%N5mm), % contrast (%QH,5mm), and contrast-to-noise ratio (QH,5mm/N5mm) for the 5 mm sphere; and coefficient of variation of the background (CVbackground) were calculated. Subsequently, clinical cases were analysed. Tumour-to-background ratios (TBRs) between breast cancer near the chest wall (close to the detector’s edge; peripheral group) and at other locations (non-peripheral group) were compared. The TBR of each lesion was compared between dbPET and PET/computed tomography (CT).Results: Closer to the detector’s edge, the %N5mm and CVbackground increased and %QH,5mm and QH,5mm/N5mm decreased in the phantom study. The disadvantages of this placement were visually confirmed. Regarding clinical images, TBR of dbPET was significantly higher than that of PET/CT in both the peripheral (12.1±6.2 vs. 6.5±3.4, p=0.0001) and non-peripheral (13.1±7.1 vs. 7.7±7.4, p=0.0004) groups. There was no significant difference in TBR of dbPET between the peripheral and non-peripheral groups (12.1±6.2 vs. 13.1±7.1, p=0.6367).Conclusion: The phantom study revealed poorer image quality closer to the detector edge at a depth of 1/8 of the axial field of view (FOV) than at other more central parts. In clinical studies, however, lesion detectability of dbPET was the same regardless of the lesion position, and it was higher than that in PET/CT. dbPET has a great potential for detecting breast lesions near the chest wall if they are within the FOV, even in young women with small breasts.

Download Full-text

Evaluation of image quality at the detector’s edge of dedicated breast positron emission tomography: Can small breast cancer near the chest wall be detected ?

10.21203/rs.3.rs-21524/v1 ◽

2020 ◽

Author(s):

Yoko Satoh ◽

Utaroh Motosugi ◽

Masamichi Imai ◽

Yoshie Omiya ◽

Hiroshi Onishi

Keyword(s):

Breast Cancer ◽

Positron Emission Tomography ◽

Image Quality ◽

Chest Wall ◽

Phantom Study ◽

Emission Tomography ◽

Clinical Images ◽

Positron Emission ◽

Pet Ct ◽

Significant Difference

Abstract Purpose : We assessed image quality of dedicated breast positron emission tomography (dbPET) at the detector's edge by phantom and clinical studies.Methods: A breast phantom with four spheres (16, 10, 7.5, and 5 mm in diameter) was filled with 18 F-fluorodeoxyglucose solution of sphere-to-background ratio was 8:1. It was positioned such that the spheres were five different positions from the top edge to the centre of the detector and scanned for 5 min in each position. Reconstructed images were visually evaluated, and % background variability ( %N 5mm ), % contrast ( %Q H ,5mm ), contrast-to-noise ratio ( Q H ,5mm / N 5mm ), and coefficient of variation of the background ( CV background ) were calculated. Next, tumour-to-background ratios (TBRs) between breast cancer near the chest wall (close to the detector’s edge; peripheral group) and at other locations (non-peripheral group) were compared. The TBR of each lesion was also compared between dbPET and PET/computed tomography (CT).Results: As closer to the detector’s edge, the %N 5mm and CV background increased and %Q H ,5mm and Q H ,5mm / N 5mm decreased in the phantom study. The disadvantages of this placement were visually confirmed. With regard to clinical images, TBR of dbPET was significantly higher than that of PET/CT in both the peripheral (12.1±6.2 vs. 6.5±3.4, p =0.0001) and non-peripheral (13.1±7.1 vs. 7.7±7.4, p =0.0004) groups. There was no significant difference in TBR of dbPET between the peripheral and non-peripheral groups (12.1±6.2 vs. 13.1±7.1, p= 0.6367).Conclusion : In the phantom study, the image quality decreased closer to the detector’s edge than at a depth of 1/8. In clinical studies, however, the lesion detectability of dbPET was the same even if the lesion was close to the detector’s edge or not, and it was higher than that in PET/CT. dbPET has a great potential for detecting breast lesions near the chest wall even in young women with small breasts.

Download Full-text

Total-body 18F-FDG PET Scan in Oncological Patients: How Fast could it be?

10.21203/rs.3.rs-320600/v1 ◽

2021 ◽

Author(s):

Pengcheng Hu ◽

Yiqiu Zhang ◽

Haojun Yu ◽

Shuguang Chen ◽

Hui Tan ◽

...

Keyword(s):

Image Quality ◽

Phantom Study ◽

Pet Scan ◽

Clinical Settings ◽

Recovery Coefficient ◽

Clinical Images ◽

Oncological Patients ◽

Pet Ct ◽

Significant Difference ◽

Total Body

Abstract Purpose: The aim of the study was to explore a fast PET scan protocol of the total-body uEXPLORER scanner by assessing the image quality consistent to that of a conventional digital PET/CT scanner both from the phantom and clinical perspectives.Methods: The phantom study using a NEMA/IEC NU-2 body phantom was performed both on a total-body PET/CT (uEXPLORER) and a digital routine PET/CT (uMI 780), with hot sphere to background activity concentration ratio of 4:1. The contrast recovery coefficient (CRC), background variability (BV), recovery coefficient RCmax and RCmean were assessed and compared between that in uEXPLORER with the different scanning duration and reconstruction protocols and that in uMI 780 with clinical settings. The coefficient of variation (COV) of the uMI 780 with clinical settings were calculated and used as a threshold to determine the optimized scanning duration and reconstruction protocols were, which can provide a consistent image quality for the two scanners. And subsequently, the proposed protocol was validated by 30 oncological patients. Images acquired in uMI 780 with a 2-3 minute for each bed position were referred as G780. All PET raw data were reconstructed using data-cutting technique to simulate a 30s, 45s or 60s acquisition duration on uEXPLORER. The iterations were 2 and 3 for uEXPLORER, referred as G30s_3i, G45s_2i, G45s_3i, G60s_2i, and G60s_3i. A 5-point Likert scale was used in the qualitative analysis to assess the image quality. The image quality was also compared with the liver COV, the lesion target-to-background ratio (TBR), and the lesion signal-to-noise ratio (SNR).Results: In the phantom study, CRC, BV, RCmax and RCmean in uEXPLORER with different scanning duration and reconstruction iterations were compared with that in uMI 780 with clinical settings and a minor fluctuation was found among different scanning durations. COV of the uMI 780 with clinical settings was 11.6% and determined protocol with a 30-45s scanning duration and 2 or 3 iterations to provide a similar image quality.In the quantitative analysis on the clinical images, there was no significant difference between G780 and G45s_3i. All the other groups in uEXPLORER with a 45s- and above acquisition showed a significantly improved image quality than that in uMI 780 with clinical settings. Comparing the liver COV, there was no significantly difference between G780 and G30s_3i. And no significant difference in lesion TBR was identified between G780 and G45s_2i, while uEXPLORER had a better performance in lesion SNR compared to that in uMI 780 with clinical settings. Conclusions: This study demonstrated a fast PET protocol with a 30-45s acquisition in uEXPLORER with consistent image quality to that in uMI 780 with clinical settings.

Download Full-text

Investigation of acquisition time for harmonization of image quality between PET/CT and PET/MRI systems: A phantom study

Optik ◽

10.1016/j.ijleo.2021.167594 ◽

2021 ◽

pp. 167594

Author(s):

Seok Hwan Yoon ◽

Chan Rok Park

Keyword(s):

Image Quality ◽

Phantom Study ◽

Acquisition Time ◽

Pet Ct

Download Full-text

Does contrast-enhanced ultrasound (CEUS) play a better role in diagnosis of breast lesions with calcification? A comparison with MRI

British Journal of Radiology ◽

10.1259/bjr.20200195 ◽

2020 ◽

Vol 93 (1112) ◽

pp. 20200195

Author(s):

Jiamin Pan ◽

Wenjuan Tong ◽

Jia Luo ◽

Jinyu Liang ◽

Fushun Pan ◽

...

Keyword(s):

Breast Imaging ◽

Breast Lesions ◽

Diagnostic Efficiency ◽

Contrast Enhanced Ultrasound ◽

Roc Curve Analysis ◽

Diagnostic Efficacy ◽

Score System ◽

Contrast Enhanced ◽

Significant Difference

Objective: To compare the efficacy of contrast-enhanced ultrasound enabled reclassification of Breast Imaging Reporting and Data System (CEUS-BI-RADS) with MRI in the diagnosis of breast lesions with calcification. Methods: A total of 52 breast lesions with calcification from 51 patients were detected by ultrasound as hyperechoic foci and categorized as BI-RADS 3–5. The 51 patients further underwent CEUS scan and MRI. The ultrasound-BI-RADS combined with CEUS 5-point score system redefined the classification of BI-RADS which was called CEUS-BI-RADS. The diagnostic efficacy of three methods was assessed by receiver operating characteristic (ROC) curve analysis. Histopathological assessment used as the gold-standard. Results: The sensitivities of Ultrasound-BI-RADS, MRI classification of BI-RADS (MRI-BI-RADS) and CEUS-BI-RADS were 85%, 90% and 95% without significant difference among the three modalities (p > 0.05). The diagnostic specificities of ultrasound-BI-RADS, MRI-BI-RADS and CEUS-BI-RADS were 78.1%, 78.1% and 96.8%, respectively (p < 0.05); and the accuracy were 80.7%, 82.6% and 96.1% for ultrasound-BI-RADS, MRI-BI-RADS and CEUS-BI-RADS, respectively (p < 0.05). The area under ROC (AUROC) in differentiation of breast lesions with calcification was 0.945 for CEUS-BI-RADS, 0.907 for MRI-BI-RADS and 0.853 for ultrasound-BI-RADS, with no significant difference among the three modalities (p > 0.05). Conclusion: The CEUS-BI-RADS has a better diagnostic efficiency than MRI-BI-RADS in the differentiation of the breast lesions with calcification. Advances in knowledge: •CEUS is a better method in differentiation of breast lesions with calcification. •CEUS-BI-RADS increases the efficiency of diagnosis compared to MRI.

Download Full-text